Object recognition is an essential function of the human visual system, and is subserved by activation in the temporal lobe of the brain. People with autism display atypical object recognition and decreased temporal lobe activation, compared to controls, under some circumstances. We present preliminary data indicating that, in autism, the speed of object recognition and the accuracy of face recognition does not change from late childhood to adulthood. This contrasts with the typical developmental trajectory, which shows developmental improvement in object recognition skills into adulthood, consistent with the prolonged maturation of ventral stream areas. These results indicate that developmental processes during adolescence differ in autism compared to typical controls. Better characterization of this understudied developmental stage is crucial for understanding the differences found in autism. It is not clear what components of object recognition are impaired in autism, and how these relate to the phenotype and to underlying brain differences, including atypical temporal lobe function and its connectivity with other regions. The present application proposes to: 1) examine the late developmental changes in object recognition skills in children and adolescents with and without autism, and 2) better characterize changes in brain function related to this behavioral development, and how it differs in autism. We hypothesize that object recognition skills that mature late are more likely to be impaired in autism. Eye tracking will reveal whether people with autism use unique, possibly immature, strategies on many of these tasks. Neuroimaging studies will examine whether people with autism display an immature pattern of brain function, or utilize a distinct network. These studies will help identify the neural bases for atypical face recognition in autism, begin to delineate the range of deficits, and examine the developmental trajectory of these skills. More generally, describing the function in temporal lobe areas during this late development, and identifying the impact on behavior,will provide important information about how development and experience changes brain organization. These developmental changes in brain organization may affect those with neurodevelopmental disorders, as well as psychopathologies that emerge during late childhood and adolescence.